It is one of the main concerns of protection of shock sensitive items such as electronic products during delivery. The products are packed by packing device such as polystyrene foam or paperboard. In order to reduce the risk of impact during transportation, the packing device has to be made thick enough so as to provide a cushion feature for the products. Nevertheless, the bulky packing device occupies too much space and the products are not easily to be positioned or fixed. If the packing device, such as paperboard, is made to be thin to save more space for the product, it has less ability of anti-shake feature and tends to be peeled off that affects the products to be packed. Besides, the conventional packing devices cannot be overlapped and this is inconvenient for the packers. Besides, for the electronic industry, one of the important factors of the cost of manufacturing is the time of assembly. A better-designed packing device reduces the time of packing. Generally, most of the electronic products are precious so that it is the main concerns to pack the maximum quantity of product within limited space and to deliver the product to its destinations. A conventional packing device 1 is shown in FIG. 1 and includes a top board 11 having separation plates 111 and a bottom board 12 having a bottom plate 124 and a plurality of side boards 121, 122, 123. Each of the side boards 121, 122, 123 has separation plates 125. The bottom plate 124 is first put in to a box 99 and the products 100 are put along the separation plates 125, and finally the top board 11 is covered on the side boards 121, 122, 123. The products 100 are not well positioned and could be hit with each other or hit by object from outside of the box 99.
Therefore, it is desired to have a proper packing device that provides well positioning and cushion features so as to provide protection to the products.